In 1 kilobytes there are 1,000 bytes. Meanwhile in 1 bytes there are 0.001 kilobytes. Keep reading to learn more about each unit of measure and how they are calculated. Or just use the Bytes to Kilobytes calculator above to convert any number.
* Values rounded to 6 decimal places for readability
To convert kilobytes (KB) to bytes (B), multiply the number of kilobytes by 1,024.
This works for the common binary file size standard used in most computer storage and memory.
It depends on which standard you use. In most everyday file sizes, 1 kilobyte (KB) = 1,000 bytes. In some computer memory contexts, people use 1 KB = 1,024 bytes, but that value is more accurate for kibibytes (KiB).
KB (kilobyte) usually means 1,000 bytes (base-10).
KiB (kibibyte) means 1,024 bytes (base-2).
KiB is the clearer term when you mean 1,024 bytes.
Computers work in base-2, so sizes often land on powers of two. For a long time, many systems used “KB” to mean 1,024 bytes out of habit. Today, KiB is the correct name for 1,024 bytes, while KB is most often 1,000 bytes.
Use one of these based on the standard you need:
Using the common decimal standard:
5 KB = 5 × 1,000 = 5,000 bytes
If you mean the binary amount:
5 KB (as 1,024-byte units) = 5 × 1,024 = 5,120 bytes
Using decimal KB:
100 KB = 100 × 1,000 = 100,000 bytes
Using binary units:
100 × 1,024 = 102,400 bytes
In decimal units, yes: 1 KB = 1,000 bytes.
If you see 1 KB used as 1,024 bytes, that’s using the binary convention (more correctly 1 KiB).
Use 1,000 when talking about file sizes in storage and downloads, since many systems label those in decimal KB. Use 1,024 when you’re working with memory, low-level computing, or when a tool clearly uses binary units.
Using decimal KB:
1,024 KB = 1,024,000 bytes
Using binary units:
1,024 × 1,024 = 1,048,576 bytes (this equals 1 MiB in binary terms)
Yes. KB means kilobytes. Kb means kilobits.
A byte is 8 bits, so mixing these can cause big mistakes.
Multiply the KB value by the right factor:
Example (decimal): 2.5 KB = 2.5 × 1,000 = 2,500 bytes
Some systems show sizes using 1,000-based units, while others use 1,024-based units. The label may still say “KB,” even when the math differs. That’s why the same file can show slightly different KB values.
A byte is smaller. A kilobyte is a group of bytes:
The Calculate Box tool to convert kilobytes to bytes uses the open source script Convert.js to convert units of measurement. To use this tool, simply type a kilobytes value in the box and have it instantly converted to bytes.